Help on merging two excel data sources

Hi Everyone,

I have below questions on merging of 2 excel data sources, can you please help me how to resolve:

Q1) Can we merge on more than one unique Column

Q2) I am merging two excel data sources based on one column, lets say Employee Number. This Employee Number is unique in first excel data source

      but the values of Employee Number are repeating in second excel data source, in this case how to merge using SAP - Lumira

Thanks,

Sankar